Uridine is the main source of cytidinetriphosphate (CTP) for the brain cells, since it can cross the blood-brain barrier and be phosphorylated to UTP, which in turn can be aminated to CTP [17].

In this study, we determined the structural and biochemical factors that govern how analogues of NTPs (ATP, CTP, GTP, and UTP) and different nucleic acids (single-stranded [ss] RNA, ssDNA, ...